1. Field of the Invention
The present invention is directed to a switch matrix of the type having a set of inputs and a set of outputs, with controllable switch elements and a conductor arrangement that is connected to the inputs and outputs and to the controllable switch elements to set a signal path between an input and an output dependent on the states of the controllable switch elements.
2. Description of the Prior Art
A switch matrix of the type described above is disclosed in European Application EP 0 138 637.
With such a switch matrix, an input can be connected to an arbitrary output in order to forward an input signal to a selected output. Such a switch matrix can be employed in a diagnostic magnetic resonance apparatus in order to connect various reception antennas to specific signal processing channels. The reception antennas can be a number of a plurality of small local antennas (array antennas) lying next to one another, whose simultaneously received signals are evaluated in order to achieve a high signal-to-noise ratio. The reception signals of the individual local antennas are usually forwarded to separate evaluation channels and combined as digital signals in the image calculation. A combination of a number of reception signals before they are digitized is implemented, for example, when fewer evaluation channels than signaling reception channels are available in a magnetic resonance apparatus. An antenna array with switchable individual antennas and a signal combiner is disclosed in European Application 0 390 476. In the operation of this known arrangement, however, special steps must be taken to assure that all reception channels modify the phase position of the reception signals in the same way.